linux-kernel - Re: [RFC v2] /dev/iommu uAPI proposal

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 6 Aug 2021 14:47:50 +1000
From:   David Gibson <david@...son.dropbear.id.au>
To:     Jason Gunthorpe <jgg@...dia.com>
Cc:     "Tian, Kevin" <kevin.tian@...el.com>,
        "Alex Williamson (alex.williamson@...hat.com)" 
        <alex.williamson@...hat.com>,
        Jean-Philippe Brucker <jean-philippe@...aro.org>,
        Jason Wang <jasowang@...hat.com>,
        "parav@...lanox.com" <parav@...lanox.com>,
        "Enrico Weigelt, metux IT consult" <lkml@...ux.net>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Shenming Lu <lushenming@...wei.com>,
        Joerg Roedel <joro@...tes.org>,
        Eric Auger <eric.auger@...hat.com>,
        Jonathan Corbet <corbet@....net>,
        "Raj, Ashok" <ashok.raj@...el.com>,
        "Liu, Yi L" <yi.l.liu@...el.com>, "Wu, Hao" <hao.wu@...el.com>,
        "Jiang, Dave" <dave.jiang@...el.com>,
        Jacob Pan <jacob.jun.pan@...ux.intel.com>,
        Kirti Wankhede <kwankhede@...dia.com>,
        Robin Murphy <robin.murphy@....com>,
        "kvm@...r.kernel.org" <kvm@...r.kernel.org>,
        "iommu@...ts.linux-foundation.org" <iommu@...ts.linux-foundation.org>,
        David Woodhouse <dwmw2@...radead.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Lu Baolu <baolu.lu@...ux.intel.com>
Subject: Re: [RFC v2] /dev/iommu uAPI proposal

On Wed, Aug 04, 2021 at 11:04:47AM -0300, Jason Gunthorpe wrote:
> On Mon, Aug 02, 2021 at 02:49:44AM +0000, Tian, Kevin wrote:
> 
> > Can you elaborate? IMO the user only cares about the label (device cookie 
> > plus optional vPASID) which is generated by itself when doing the attaching
> > call, and expects this virtual label being used in various spots (invalidation,
> > page fault, etc.). How the system labels the traffic (the physical RID or RID+
> > PASID) should be completely invisible to userspace.
> 
> I don't think that is true if the vIOMMU driver is also emulating
> PASID. Presumably the same is true for other PASID-like schemes.

Right.  The idea for an SVA capable vIOMMU in my scheme is that the
hypervisor would set up an IOAS of address type "PASID+address" with
the mappings made by the guest according to its vIOMMU semantics.
Then SVA capable devices would be plugged into that IOAS by using
"PASID+address" type endpoints from those devices.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)